The disclosure relates generally to the field of radio-frequency identification (RFID) and particularly to the bulk commissioning of RFID tags.
RFID tags may be programmed in any of a variety of ways. Many tags are capable of self-programming through the use of an air communications protocol that includes a write command and onboard permanent or semi--permanent memory writing capability. Data can be stored on these tags by establishing a communication link to the reader, issuing the write command, and waiting for the tag to complete its programming.
RFID tags may be active (i.e., having their own power source, such as a battery), or passive (i.e., relying on power received from the reader), or some combination of active and passive. Passive tags typically require that they receive signal from the reader continuously during the write process. Loss of transmission can mean loss of power and therefore a failure in writing the particular data to memory. To inform the reader of the status of an attempted write, passive tags typically respond with a notification to the reader once writing is complete.
The efficiency of utilization readers for the programming of large numbers of tags depends upon the manner in which communications between the readers and the tags is conducted and coordinated. This disclosure relates to a new method for ensuring rapid and effective programming utilizing plural regulatory communications bands.
U.S. Pat. No. 7,659,822 (Carrender, et al.), titled “Method and apparatus for testing RFID devices”, describes a method and apparatus for testing RFID straps. Arrays of RFID straps in a roll-to-roil process are coupled to an array of test elements. RF programming and interrogation signals are frequency and time multiplexed to the RFID array. Return signals are detected to determine sensitivity and programmability parameters of the RFID straps. In one embodiment, the signal sources may be RFID readers or transceivers configured to operate at m different frequency channels within an RFID band. Further, these frequencies may be chosen to maximize the frequency separation of nearest columns of test elements and next nearest columns in a specified operating frequency band.
U.S. Patent Application US 200910303016 A1 (Deuber. et al.), titled “Method for commissioning an RFID network”, describes a method for implementing an RFID network whereby: each read-write station transmits at least one test signal; each read-write station receives the (receivable) test signals of neighboring read-write stations, said signals comprising a station address, a frequency channel number and a measured signal intensity of each receivable neighboring read-write station; a network structure comprising structure data and a coordination plan comprising co-ordination data are calculated using a number of time slots and a number of frequency channels, as service frequency channel (reader service channel, RSK) and/or a service time slot (reader service time, RST) being defined and used by the read-write stations for service purposes; and at least corresponding structure data and co-ordination data for an organized, synchronous network operation is transmitted to the read-write stations so that said stations do not interfere with one another.
The inventor notes that such prior solutions fail to take advantage of plural regulatory bands for communication being available. Under the proper circumstances, all bands may be used in a single jurisdiction. To use the Japanese band in the United States, in addition to the U.S. band, it is merely necessary, for instance, to either obtain an emissions waiver tear the appropriate governmental authorities, distance the broadcast equipment from devices in danger of interference, or shield the emission from radiating away from the area of interest. RFID tags requiring bulk commissioning are often located in very confined space which may be shielded with relative ease. The inventive concept includes taking advantage of plural regulatory bands at as single installation.